JP3133560B2 - Control method of digital car telephone system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a digital car telephone system.

[0002]

2. Description of the Related Art Digital car telephone systems are described in "Digital Car Phone System Standards (RCR ST
D-27)). The operation of the mobile station after the power is turned on will be described with reference to FIG.

[0003] After a power supply is turned on, a mobile station first has hardware,
After performing power-on processing 1 for initializing the software, the process proceeds to perch channel scan processing 2. In the perch channel scanning process 2, the mobile station measures all the reception levels of the perch channels stored in advance, and if there is a perch channel having a value equal to or higher than a certain threshold value (hereinafter, referred to as an effective perch channel), The process proceeds to standby channel selection processing 3.

In the standby channel selection process 3, the effective perch channels are rearranged in descending order of the reception level,
The data sent on the channel with the highest reception level is received, and it is checked whether or not the data is appropriate as a standby channel. That is, information called broadcast information is received, and it is determined whether the standby permission level or the network number is appropriate.
If it is not appropriate, it receives the data sent on the next higher level channel and also checks if it is appropriate as a standby channel. If there is an appropriate channel, the process proceeds to standby process 4. The above processing is performed until there is no more effective perch channel.

[0005] In a standby process 4, while measuring the reception level, the user waits for an outgoing call operation from the user and an incoming call from the network. When the reception level becomes poor, for example, when the reception level is not appropriate for the standby state due to the movement of the mobile station, the process returns to the perch channel scan processing 2. If there is a call operation, the process proceeds to call processing 5. If there is an incoming call, the process proceeds to incoming call processing 6.

In outgoing call processing 5 and incoming call processing 6, after information necessary for transition to communication is transmitted and received to / from the network,
The communication channel is switched to the communication channel according to the information from the network, and the process proceeds to communication processing 7. When switching to the communication channel fails, the process may return to the perch channel scanning process 2.

In communication processing 7, voice communication is performed after necessary information is transmitted / received to / from a network. The disconnection operation is performed by the own mobile station,
Or, in the case of a normal disconnection as performed by the destination,
The process returns to the standby process 4 and returns to the perch channel scan process 2 when the radio wave is interrupted and the connection is abnormally disconnected.

If it is determined that there is no valid perch channel in the perch scan processing 2 described above, or if there is no suitable channel as a standby channel in the standby channel selection processing 3, it is determined that the network is out of service. 8 is executed. Regarding out-of-service processing 8,
Although not specifically defined in the above standard, it is generally considered that the perch channel scan 2 is repeatedly executed.

[0009]

By the way, since the mobile station is assumed to move, the mobile station may move to the service area after it is determined that the mobile station is out of the service area. It is desirable to immediately enter the standby state. Therefore, even after determining that the mobile station is out of the service area, the mobile station repeatedly performs the perch channel scan processing 2. When the mobile station stays out of the service area, the perch channel scanning process is always performed, and as a result, wasteful power is consumed. In order to reduce this power consumption, after it is determined that the mobile station is out of the service area, the perch channel scan processing 2 may be performed intermittently. However, when the mobile station enters the service area, the user immediately enters the standby state. Considering convenience, the shorter the better, the better.

An object of the present invention is to solve such a problem and to quickly detect that a mobile station has moved from outside the service area to a service area and set the mobile station in a standby state, and to minimize power consumption at that time. Is what you do.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a method for moving a mobile station out of the service area when it is determined that the mobile station is located outside the service area of the digital car telephone system. In the control method of the digital car phone system which performs a perch channel scan process when measuring the reception level of the perch channel for the purpose of judging the inside / outside of the service area in order to make a transition to a communication-ready state in which transmission and reception can be performed, When it is determined that there is a channel, the mobile station selects a plurality of perch channels from the perch channels stored in advance.
Select a plurality of selected perch channels , perform intermittent simple scan processing to determine whether there is a perch channel having a reception level equal to or higher than a predetermined threshold, If there is perch channel or the reception level and the total perch channel
Execute the perch channel scan process and
If there is no reception level above,
It is characterized by intermittent repetition .

Further, according to the present invention, when it is determined that the mobile station is located outside the service area of the digital car telephone system, the mobile station shifts into the service area and shifts to a communication-ready state in which the mobile station can make and receive calls. In order to judge whether the area is within or outside the service area, the reception level of the perch channel is measured, and the perch channels having the reception level equal to or higher than a predetermined threshold are received in descending order of the reception level. In a control method for a digital car telephone system that performs a perch channel scanning process and a standby channel selection process when determining whether the channel is appropriate for standby, when performing a process of selecting one channel for standby, a channel for standby is used. While storing the perch channel determined not to be When it is determined that the mobile station is outside, the mobile station selects some perch channels from the previously stored perch channels, excluding the stored perch channel, and measures the selected perch channel reception level. Then, a simple scan process for determining whether there is a perch channel having a reception level equal to or higher than a predetermined threshold is performed intermittently, and a perch channel scan is performed when there is a perch channel having a reception level equal to or higher than a certain threshold. It is characterized by executing processing.

[0013]

When it is determined that the mobile station is located outside the service area of the mobile station, the mobile station does not measure the reception levels of all the perch channels stored in advance, but selects a predetermined one from among the previously stored perch channels. When the reception level is detected intermittently by the number of channels, and it is determined that there is a perch channel having a reception level equal to or higher than a predetermined threshold, the perch channel scanning process is performed when the reception levels are measured for all perch channels. Done.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a hardware block diagram of a mobile station implementing the present invention. The radio wave received through the antenna 9 is tuned by the RF / IF unit (reception system) 10, and the signal of the tuned channel is passed to the TDMA processing circuit (reception system) 12 through the demodulator 11. The RF / IF unit (reception system) 10 also notifies the microcomputer 13 of the reception level of the tuned channel. TDMA processing circuit (receiving system) 1
In step 2, control information and audio information are extracted from the received signal, the control information is sent to the microcomputer 13, and the audio information is sent to the D / A
Pass to circuit 14. The D / A circuit 14 converts the received digital audio information into an analog audio signal and passes it to the audio processing circuit 15. The audio processing circuit 15 that has received the analogized audio information sounds the ringer 16 or the speaker 17 according to the instruction of the microcomputer 13 based on the audio information. The audio processing circuit 15 also picks up the audio from the microphone 18, converts it into an analog signal, and passes it to the A / D circuit 19.

The analog audio information is converted into digital audio information by an A / D circuit 19 and passed to a TDMA processing circuit (transmission system) 20. TDMA processing circuit (transmission system) 2
0, the audio information from the A / D circuit 19 and the microcomputer 13
Is combined with information necessary for communication, and is transmitted as a transmission signal through a modulator 21 to an RF / IF unit (transmission system) 22. The RF / IF unit (transmission system) 22 puts the signal on a frequency specified by the PLL frequency synthesizer 23 and sends the signal to the air through the antenna 9. The PLL frequency synthesizer unit 23 gives a frequency tuning signal to the RF / IF unit (reception system) 10 or the RF / IF unit (transmission system) 22 according to an instruction from the microcomputer 13.

The display unit 24 provides a display that can be recognized by the user in accordance with an instruction from the microcomputer 13, and the key unit 25 transmits the operation of the user to the microcomputer 13. The microcomputer 13 uses R
The reception level from the F / IF unit (reception system) 10 is
The control information is obtained from the processing circuit (transmission system) 12, the operation content of the user is obtained from the key unit 25, the transmission control information is provided to the TDMA processing circuit (transmission system) 20,
While controlling the display unit 24 and the PLL frequency synthesizer unit 23, each process shown in FIG. 1 is performed to manage and control the mobile station.

FIG. 3 shows the configuration of the microcomputer 13. The microcomputer 13 includes a CPU 26 for performing each process, a ROM 27 in which a program of a processing procedure is stored, a RAM 28 in which data necessary for each process is temporarily stored and read out at appropriate times,
And interfaces 29 to 35 with each hardware
Consists of

Next, the control method of the digital car telephone system according to the present invention will be described with reference to the flowcharts of FIGS.

First, as described with reference to FIG. 1, after the power is turned on, the mobile station performs a power-on process for initial setting of hardware and software, and then performs a perch channel scan process. In the perch channel scan process,
The mobile station measures all the reception levels of the perch channels stored in advance, and if there is a valid perch channel, executes the flowchart of the standby channel selection process shown in FIG. In this standby channel selection processing,
First, the number of perch channels (effective perch channels) having a reception level value equal to or higher than a certain threshold value obtained in the perch channel scanning process in the preceding stage is set (36).
Next, the effective perch channels are rearranged in descending order of their reception levels (37). Next, the pointer of the rearranged effective perch channel array is initialized to point to the head of the array (38). Next, the perch channel indicated by the pointer is read (39). Then, the broadcast information received on the channel is received (40).

Next, the control information in the broadcast information is analyzed to determine whether the current reception channel is suitable as a standby channel, that is, whether the standby permission level or the network number is appropriate (41). ), If appropriate, go to standby processing.

If the current reception channel is not suitable as a standby channel, the current reception channel is determined to be unsuitable for standby and is stored in a list of non-standby channels (42).

Next, the number of effective perch channels set in (36) is subtracted by one (43). When the number of effective perch channels becomes 0 (44), the processing proceeds to out-of-service processing. If it is not 0, the pointer of the effective perch channel array is updated (45), and the process returns to (39).

The out-of-service processing is executed according to the flowchart shown in FIG. That is, first, a wait timer is initialized to make a certain waiting time (4.
6). This wait timer is an interrupt process executed at regular intervals, and is decremented by one.
Wait until (47).

Next, when the reception level is measured, the number of perch channels is set (48). That is, assuming that the number of channels to be scanned at one time in the intermittent perch channel scan is, for example, four, a value of 4 is set as the counter value as the number of perch channels.

Next, when the present reception level of the perch channel array stored in the ROM is measured, the value of the pointer indicating the perch channel is read (49). This pointer is initialized to 0 when the power is turned on, and is updated by the processing described below. Next, the perch channel indicated by the pointer is read (50). Next, this pointer is updated (51).

Next, it is checked whether or not the perch channel thus read is included in the list of non-standby channels (52). If it is included, the process returns to (49). If not, the reception level of the channel is measured (53). If the measured reception level is higher than a certain threshold (54), it is determined that the mobile station has already entered the service area, and the process proceeds to the perch channel scanning process.

Otherwise, when the present reception level set in (48) is measured, the number of perch channels is decremented by one (55). If the number of perch channels is not 0 (5
6) Return to (49). If it is 0, the process returns to the beginning of the out-of-service processing.

When the processing is performed according to such a flowchart, if it is determined that the mobile station is located outside the service area, the reception level is intermittently changed by the preset number of channels (four channels in this embodiment). Measured. At this time, the reception level is measured without the perch channel determined to be not the standby channel in the standby channel selection processing at the time of power-on.

For example, assuming that the present invention is not applied to a mobile station in which 100 perch channels are stored in the ROM in advance and that the present invention is applied, the following is obtained.

Assuming that it takes 5 ms to measure the reception level of one perch channel, it takes 500 ms to measure the reception level of all the perch channels. If it is determined that the mobile station is out of the service area and if no weight is applied until the next perch channel scan processing is performed, the perch channel scan processing is always performed if this 500 ms is required.

If it is determined that the mobile station is out of the service area and a weight of 49.5 seconds is applied, the power consumption when the mobile station is out of the service area (out of the service area) is 1/100 on average. However, power consumption other than that used for measuring the reception level is ignored for ease of consideration.

However, in this case, when the mobile station moves from the outside of the service area to the inside of the service area, the mobile station cannot enter the standby state for a maximum of 50 seconds. This is not preferable considering the convenience of the user.

Considering the case where the present invention is applied to the above-described mobile station, when the reception levels of four perch channels are measured every 1.98 seconds in out-of-service processing, the average when the mobile station is out of the service area is calculated. Power consumption is the same as above. However, since the reception level of the perch channel is measured every 1.98 seconds, when the mobile station enters the service area from outside the service area, it can be expected that the mobile station will be in the standby state more quickly, which is convenient for the user. Increase. In particular, if the perch channel is selected when the reception level is detected at the same time in the out-of-service processing in consideration of the allocation of the perch channel in each service area, the expected value of the quicker transition to the standby state increases.

Furthermore, by excluding perch channels which are effective in reception level but are unsuitable for a standby channel from reception level measurement in out-of-service processing,
This is useful for avoiding unnecessary perch channel scan processing, and is thus effective in further reducing power consumption. In addition, since measuring the reception level can reduce the total number of perch channels, it is possible to expect a faster transition to the standby state when the mobile station moves from outside the service area to inside the service area.

[0035]

As described above, according to the control method of the digital car telephone system of the present invention, it is possible to quickly detect that the mobile station has moved from the outside of the service area to the service area and set the mobile station to the standby state. Power consumption can be reduced as much as possible.

[Brief description of the drawings]

FIG. 1 is a schematic flowchart of processing of a mobile station.

FIG. 2 is a block diagram of a digital car telephone system according to the present invention.

FIG. 3 is a block diagram of a microcomputer of the digital car telephone system according to the present invention.

FIG. 4 is a flowchart showing a control method of a standby channel selection process of the digital car telephone system according to the present invention.

FIG. 5 is a flowchart showing a control method of out-of-service processing of the digital car telephone system according to the present invention.

[Explanation of symbols]

 1 Mobile station power-on processing 2 Perch channel scan processing 3 Standby channel selection processing 4 Mobile station standby processing 5 Mobile station transmission processing 6 Mobile station incoming processing 7 Mobile station communication processing 8 Mobile station Out of service processing 18 Antenna 19 RF / IF unit (Reception system) 20 Demodulator 21 TDMA processing circuit (Reception system) 22 Microcomputer 23 D / A circuit 24 Audio processing circuit 25 Ringer 26 Speaker 27 Microphone 28 A / D circuit 29 TDMA Processing circuit (transmission system) 30 Modulator 31 RF / IF unit (transmission system) 32 PLL frequency synthesizer unit 33 Display unit 34 Key unit 35 CPU 36 ROM 37 RAM 38 TDMA processing circuit (reception system) interface 39 TDMA processing circuit (transmission) System) interface 40 RF / IF section (reception system) interface Over scan 41 display unit interface 42 key unit interface 43 PLL frequency synthesizer unit interface 44 audio processing circuit interface

Claims (2)

(57) [Claims] When it is determined that the mobile station is located outside the service area of the digital type mobile telephone system, the mobile station moves out of the service area and enters a communication standby state where the mobile station can make and receive calls. In a control method of a digital car telephone system for performing a perch channel scan process by measuring a perch channel reception level for the purpose of judging out of service, a perch channel stored in advance by a mobile station when it is determined that the mobile station is out of service. Perch multiple from among
Intermittently perform a simple scan process of measuring the reception level of the selected plurality of perch channels and determining whether there is a perch channel having a reception level equal to or higher than a predetermined threshold. And if there is a perch channel with a reception level equal to or higher than a certain threshold ,
Performs perch channel scan processing on the
If there is no reception level above the threshold, the above simple scan
A digital car telephone system characterized by intermittently repeating processing . 2. When the mobile station is determined to be located outside the service area of the digital car telephone system, the mobile station shifts to the service area and shifts to a communication-ready state in which the mobile station can make and receive calls. The reception level of the perch channel is measured for the purpose of judging the inside / out of service area, and the perch channels having the reception level equal to or higher than a predetermined threshold are received in descending order of the reception level. In the control method of the digital car phone system that executes the perch channel scanning process and the standby channel selection process when determining whether the channel is appropriate or not, when performing the process of selecting one of the standby channels, it is determined that the channel is not the standby channel. The perch channel determined is memorized, and it is determined that the Then, the mobile station selects some perch channels from the previously stored perch channels, excluding the stored perch channels, measures the selected perch channel reception level, A simple scan process for determining whether there is a perch channel having a reception level equal to or higher than a threshold value is performed intermittently, and a perch channel scan process is performed when there is a perch channel having a reception level equal to or higher than a certain threshold value Control method for digital car telephone system characterized by the following: